( function () {

    // Unlike TrackballControls, it maintains the "up" direction object.up (+Y by default).
    //
    //    Orbit - left mouse / touch: one-finger move
    //    Zoom - middle mouse, or mousewheel / touch: two-finger spread or squish
    //    Pan - right mouse, or left mouse + ctrl/meta/shiftKey, or arrow keys / touch: two-finger move

    const _changeEvent = {
        type: 'change'
    };
    const _startEvent = {
        type: 'start'
    };
    const _endEvent = {
        type: 'end'
    };

    class OrbitControls extends THREE.EventDispatcher {

        constructor( object, domElement ) {

            super();
            if ( domElement === undefined ) console.warn( 'THREE.OrbitControls: The second parameter "domElement" is now mandatory.' );
            if ( domElement === document ) console.error( 'THREE.OrbitControls: "document" should not be used as the target "domElement". Please use "renderer.domElement" instead.' );
            this.object = object;
            this.domElement = domElement;
            this.domElement.style.touchAction = 'none'; // disable touch scroll
            // Set to false to disable this control

            this.enabled = true; // "target" sets the location of focus, where the object orbits around

            this.target = new THREE.Vector3(); // How far you can dolly in and out ( PerspectiveCamera only )

            this.minDistance = 0;
            this.maxDistance = Infinity; // How far you can zoom in and out ( OrthographicCamera only )

            this.minZoom = 0;
            this.maxZoom = Infinity; // How far you can orbit vertically, upper and lower limits.
            // Range is 0 to Math.PI radians.

            this.minPolarAngle = 0; // radians

            this.maxPolarAngle = Math.PI; // radians
            // How far you can orbit horizontally, upper and lower limits.
            // If set, the interval [ min, max ] must be a sub-interval of [ - 2 PI, 2 PI ], with ( max - min < 2 PI )

            this.minAzimuthAngle = - Infinity; // radians

            this.maxAzimuthAngle = Infinity; // radians
            // Set to true to enable damping (inertia)
            // If damping is enabled, you must call controls.update() in your animation loop

            this.enableDamping = false;
            this.dampingFactor = 0.05; // This option actually enables dollying in and out; left as "zoom" for backwards compatibility.
            // Set to false to disable zooming

            this.enableZoom = true;
            this.zoomSpeed = 1.0; // Set to false to disable rotating

            this.enableRotate = true;
            this.rotateSpeed = 1.0; // Set to false to disable panning

            this.enablePan = true;
            this.panSpeed = 1.0;
            this.screenSpacePanning = true; // if false, pan orthogonal to world-space direction camera.up

            this.keyPanSpeed = 7.0; // pixels moved per arrow key push
            // Set to true to automatically rotate around the target
            // If auto-rotate is enabled, you must call controls.update() in your animation loop

            this.autoRotate = false;
            this.autoRotateSpeed = 2.0; // 30 seconds per orbit when fps is 60
            // The four arrow keys

            this.keys = {
                LEFT: 'ArrowLeft',
                UP: 'ArrowUp',
                RIGHT: 'ArrowRight',
                BOTTOM: 'ArrowDown'
            }; // Mouse buttons

            this.mouseButtons = {
                LEFT: THREE.MOUSE.ROTATE,
                MIDDLE: THREE.MOUSE.DOLLY,
                RIGHT: THREE.MOUSE.PAN
            }; // Touch fingers

            this.touches = {
                ONE: THREE.TOUCH.ROTATE,
                TWO: THREE.TOUCH.DOLLY_PAN
            }; // for reset

            this.target0 = this.target.clone();
            this.position0 = this.object.position.clone();
            this.zoom0 = this.object.zoom; // the target DOM element for key events

            this._domElementKeyEvents = null; //
            // public methods
            //

            this.getPolarAngle = function () {

                return spherical.phi;

            };

            this.getAzimuthalAngle = function () {

                return spherical.theta;

            };

            this.getDistance = function () {

                return this.object.position.distanceTo( this.target );

            };

            this.listenToKeyEvents = function ( domElement ) {

                domElement.addEventListener( 'keydown', onKeyDown );
                this._domElementKeyEvents = domElement;

            };

            this.saveState = function () {

                scope.target0.copy( scope.target );
                scope.position0.copy( scope.object.position );
                scope.zoom0 = scope.object.zoom;

            };
            this.rotateLeft = function(angle){
                sphericalDelta.theta -= angle;
            }

            this.zoomIn = function ( zoomScale ) {
                if ( zoomScale === undefined ) {
                    zoomScale = getZoomScale()-0.1;
                }
                dollyIn(zoomScale);

            };


            this.zoomOut = function ( zoomScale ) {
                if ( zoomScale === undefined ) {
                    zoomScale = getZoomScale();
                }
                dollyOut(zoomScale);
            };

            this.reset = function () {

                scope.target.copy( scope.target0 );
                scope.object.position.copy( scope.position0 );
                scope.object.zoom = scope.zoom0;
                scope.object.updateProjectionMatrix();
                scope.dispatchEvent( _changeEvent );
                scope.update();
                state = STATE.NONE;

            }; // this method is exposed, but perhaps it would be better if we can make it private...


            this.update = function () {

                const offset = new THREE.Vector3(); // so camera.up is the orbit axis

                const quat = new THREE.Quaternion().setFromUnitVectors( object.up, new THREE.Vector3( 0, 1, 0 ) );
                const quatInverse = quat.clone().invert();
                const lastPosition = new THREE.Vector3();
                const lastQuaternion = new THREE.Quaternion();
                const twoPI = 2 * Math.PI;
                return function update() {

                    const position = scope.object.position;
                    offset.copy( position ).sub( scope.target ); // rotate offset to "y-axis-is-up" space

                    offset.applyQuaternion( quat ); // angle from z-axis around y-axis

                    spherical.setFromVector3( offset );

                    if ( scope.autoRotate && state === STATE.NONE ) {

                        rotateLeft( getAutoRotationAngle() );

                    }

                    if ( scope.enableDamping ) {

                        spherical.theta += sphericalDelta.theta * scope.dampingFactor;
                        spherical.phi += sphericalDelta.phi * scope.dampingFactor;

                    } else {

                        spherical.theta += sphericalDelta.theta;
                        spherical.phi += sphericalDelta.phi;

                    } // restrict theta to be between desired limits


                    let min = scope.minAzimuthAngle;
                    let max = scope.maxAzimuthAngle;

                    if ( isFinite( min ) && isFinite( max ) ) {

                        if ( min < - Math.PI ) min += twoPI; else if ( min > Math.PI ) min -= twoPI;
                        if ( max < - Math.PI ) max += twoPI; else if ( max > Math.PI ) max -= twoPI;

                        if ( min <= max ) {

                            spherical.theta = Math.max( min, Math.min( max, spherical.theta ) );

                        } else {

                            spherical.theta = spherical.theta > ( min + max ) / 2 ? Math.max( min, spherical.theta ) : Math.min( max, spherical.theta );

                        }

                    } // restrict phi to be between desired limits


                    spherical.phi = Math.max( scope.minPolarAngle, Math.min( scope.maxPolarAngle, spherical.phi ) );
                    spherical.makeSafe();
                    spherical.radius *= scale; // restrict radius to be between desired limits

                    spherical.radius = Math.max( scope.minDistance, Math.min( scope.maxDistance, spherical.radius ) ); // move target to panned location

                    if ( scope.enableDamping === true ) {

                        scope.target.addScaledVector( panOffset, scope.dampingFactor );

                    } else {

                        scope.target.add( panOffset );

                    }

                    offset.setFromSpherical( spherical ); // rotate offset back to "camera-up-vector-is-up" space

                    offset.applyQuaternion( quatInverse );
                    position.copy( scope.target ).add( offset );
                    scope.object.lookAt( scope.target );

                    if ( scope.enableDamping === true ) {

                        sphericalDelta.theta *= 1 - scope.dampingFactor;
                        sphericalDelta.phi *= 1 - scope.dampingFactor;
                        panOffset.multiplyScalar( 1 - scope.dampingFactor );

                    } else {

                        sphericalDelta.set( 0, 0, 0 );
                        panOffset.set( 0, 0, 0 );

                    }

                    scale = 1; // update condition is:
                    // min(camera displacement, camera rotation in radians)^2 > EPS
                    // using small-angle approximation cos(x/2) = 1 - x^2 / 8

                    if ( zoomChanged || lastPosition.distanceToSquared( scope.object.position ) > EPS || 8 * ( 1 - lastQuaternion.dot( scope.object.quaternion ) ) > EPS ) {

                        scope.dispatchEvent( _changeEvent );
                        lastPosition.copy( scope.object.position );
                        lastQuaternion.copy( scope.object.quaternion );
                        zoomChanged = false;
                        return true;

                    }

                    return false;

                };

            }();

            this.dispose = function () {

                scope.domElement.removeEventListener( 'contextmenu', onContextMenu );
                scope.domElement.removeEventListener( 'pointerdown', onPointerDown );
                scope.domElement.removeEventListener( 'pointercancel', onPointerCancel );
                scope.domElement.removeEventListener( 'wheel', onMouseWheel );
                scope.domElement.removeEventListener( 'pointermove', onPointerMove );
                scope.domElement.removeEventListener( 'pointerup', onPointerUp );

                if ( scope._domElementKeyEvents !== null ) {

                    scope._domElementKeyEvents.removeEventListener( 'keydown', onKeyDown );

                } //scope.dispatchEvent( { type: 'dispose' } ); // should this be added here?

            }; //
            // internals
            //


            const scope = this;
            const STATE = {
                NONE: - 1,
                ROTATE: 0,
                DOLLY: 1,
                PAN: 2,
                TOUCH_ROTATE: 3,
                TOUCH_PAN: 4,
                TOUCH_DOLLY_PAN: 5,
                TOUCH_DOLLY_ROTATE: 6
            };
            let state = STATE.NONE;
            const EPS = 0.000001; // current position in spherical coordinates

            const spherical = new THREE.Spherical();
            const sphericalDelta = new THREE.Spherical();
            let scale = 1;
            const panOffset = new THREE.Vector3();
            let zoomChanged = false;
            const rotateStart = new THREE.Vector2();
            const rotateEnd = new THREE.Vector2();
            const rotateDelta = new THREE.Vector2();
            const panStart = new THREE.Vector2();
            const panEnd = new THREE.Vector2();
            const panDelta = new THREE.Vector2();
            const dollyStart = new THREE.Vector2();
            const dollyEnd = new THREE.Vector2();
            const dollyDelta = new THREE.Vector2();
            const pointers = [];
            const pointerPositions = {};

            function getAutoRotationAngle() {

                return 2 * Math.PI / 60 / 60 * scope.autoRotateSpeed;

            }

            function getZoomScale() {

                return Math.pow( 0.95, scope.zoomSpeed );

            }

            function rotateLeft( angle ) {

                sphericalDelta.theta -= angle;

            }

            function rotateUp( angle ) {

                sphericalDelta.phi -= angle;

            }

            const panLeft = function () {

                const v = new THREE.Vector3();
                return function panLeft( distance, objectMatrix ) {

                    v.setFromMatrixColumn( objectMatrix, 0 ); // get X column of objectMatrix

                    v.multiplyScalar( - distance );
                    panOffset.add( v );

                };

            }();

            const panUp = function () {

                const v = new THREE.Vector3();
                return function panUp( distance, objectMatrix ) {

                    if ( scope.screenSpacePanning === true ) {

                        v.setFromMatrixColumn( objectMatrix, 1 );

                    } else {

                        v.setFromMatrixColumn( objectMatrix, 0 );
                        v.crossVectors( scope.object.up, v );

                    }

                    v.multiplyScalar( distance );
                    panOffset.add( v );

                };

            }(); // deltaX and deltaY are in pixels; right and down are positive


            const pan = function () {

                const offset = new THREE.Vector3();
                return function pan( deltaX, deltaY ) {

                    const element = scope.domElement;

                    if ( scope.object.isPerspectiveCamera ) {

                        // perspective
                        const position = scope.object.position;
                        offset.copy( position ).sub( scope.target );
                        let targetDistance = offset.length(); // half of the fov is center to top of screen

                        targetDistance *= Math.tan( scope.object.fov / 2 * Math.PI / 180.0 ); // we use only clientHeight here so aspect ratio does not distort speed

                        panLeft( 2 * deltaX * targetDistance / element.clientHeight, scope.object.matrix );
                        panUp( 2 * deltaY * targetDistance / element.clientHeight, scope.object.matrix );

                    } else if ( scope.object.isOrthographicCamera ) {

                        // orthographic
                        panLeft( deltaX * ( scope.object.right - scope.object.left ) / scope.object.zoom / element.clientWidth, scope.object.matrix );
                        panUp( deltaY * ( scope.object.top - scope.object.bottom ) / scope.object.zoom / element.clientHeight, scope.object.matrix );

                    } else {

                        // camera neither orthographic nor perspective
                        console.warn( 'WARNING: OrbitControls.js encountered an unknown camera type - pan disabled.' );
                        scope.enablePan = false;

                    }

                };

            }();

            function dollyOut( dollyScale ) {

                if ( scope.object.isPerspectiveCamera ) {

                    scale /= dollyScale;

                } else if ( scope.object.isOrthographicCamera ) {

                    scope.object.zoom = Math.max( scope.minZoom, Math.min( scope.maxZoom, scope.object.zoom * dollyScale ) );
                    scope.object.updateProjectionMatrix();
                    zoomChanged = true;

                } else {

                    console.warn( 'WARNING: OrbitControls.js encountered an unknown camera type - dolly/zoom disabled.' );
                    scope.enableZoom = false;

                }

            }

            function dollyIn( dollyScale ) {

                if ( scope.object.isPerspectiveCamera ) {

                    scale *= dollyScale;

                } else if ( scope.object.isOrthographicCamera ) {

                    scope.object.zoom = Math.max( scope.minZoom, Math.min( scope.maxZoom, scope.object.zoom / dollyScale ) );
                    scope.object.updateProjectionMatrix();
                    zoomChanged = true;

                } else {

                    console.warn( 'WARNING: OrbitControls.js encountered an unknown camera type - dolly/zoom disabled.' );
                    scope.enableZoom = false;

                }

            } //
            // event callbacks - update the object state
            //


            function handleMouseDownRotate( event ) {

                rotateStart.set( event.clientX, event.clientY );

            }

            function handleMouseDownDolly( event ) {

                dollyStart.set( event.clientX, event.clientY );

            }

            function handleMouseDownPan( event ) {

                panStart.set( event.clientX, event.clientY );

            }

            function handleMouseMoveRotate( event ) {

                rotateEnd.set( event.clientX, event.clientY );
                rotateDelta.subVectors( rotateEnd, rotateStart ).multiplyScalar( scope.rotateSpeed );
                const element = scope.domElement;
                rotateLeft( 2 * Math.PI * rotateDelta.x / element.clientHeight ); // yes, height

                rotateUp( 2 * Math.PI * rotateDelta.y / element.clientHeight );
                rotateStart.copy( rotateEnd );
                scope.update();

            }

            function handleMouseMoveDolly( event ) {

                dollyEnd.set( event.clientX, event.clientY );
                dollyDelta.subVectors( dollyEnd, dollyStart );

                if ( dollyDelta.y > 0 ) {

                    dollyOut( getZoomScale() );

                } else if ( dollyDelta.y < 0 ) {

                    dollyIn( getZoomScale() );

                }

                dollyStart.copy( dollyEnd );
                scope.update();

            }

            function handleMouseMovePan( event ) {

                panEnd.set( event.clientX, event.clientY );
                panDelta.subVectors( panEnd, panStart ).multiplyScalar( scope.panSpeed );
                pan( panDelta.x, panDelta.y );
                panStart.copy( panEnd );
                scope.update();

            }

            function handleMouseUp( ) { // no-op
            }

            function handleMouseWheel( event ) {

                if ( event.deltaY < 0 ) {

                    dollyIn( getZoomScale() );

                } else if ( event.deltaY > 0 ) {

                    dollyOut( getZoomScale() );

                }

                scope.update();

            }

            function handleKeyDown( event ) {

                let needsUpdate = false;

                switch ( event.code ) {

                    case scope.keys.UP:
                        pan( 0, scope.keyPanSpeed );
                        needsUpdate = true;
                        break;

                    case scope.keys.BOTTOM:
                        pan( 0, - scope.keyPanSpeed );
                        needsUpdate = true;
                        break;

                    case scope.keys.LEFT:
                        pan( scope.keyPanSpeed, 0 );
                        needsUpdate = true;
                        break;

                    case scope.keys.RIGHT:
                        pan( - scope.keyPanSpeed, 0 );
                        needsUpdate = true;
                        break;

                }

                if ( needsUpdate ) {

                    // prevent the browser from scrolling on cursor keys
                    event.preventDefault();
                    scope.update();

                }

            }

            function handleTouchStartRotate() {

                if ( pointers.length === 1 ) {

                    rotateStart.set( pointers[ 0 ].pageX, pointers[ 0 ].pageY );

                } else {

                    const x = 0.5 * ( pointers[ 0 ].pageX + pointers[ 1 ].pageX );
                    const y = 0.5 * ( pointers[ 0 ].pageY + pointers[ 1 ].pageY );
                    rotateStart.set( x, y );

                }

            }

            function handleTouchStartPan() {

                if ( pointers.length === 1 ) {

                    panStart.set( pointers[ 0 ].pageX, pointers[ 0 ].pageY );

                } else {

                    const x = 0.5 * ( pointers[ 0 ].pageX + pointers[ 1 ].pageX );
                    const y = 0.5 * ( pointers[ 0 ].pageY + pointers[ 1 ].pageY );
                    panStart.set( x, y );

                }

            }

            function handleTouchStartDolly() {

                const dx = pointers[ 0 ].pageX - pointers[ 1 ].pageX;
                const dy = pointers[ 0 ].pageY - pointers[ 1 ].pageY;
                const distance = Math.sqrt( dx * dx + dy * dy );
                dollyStart.set( 0, distance );

            }

            function handleTouchStartDollyPan() {

                if ( scope.enableZoom ) handleTouchStartDolly();
                if ( scope.enablePan ) handleTouchStartPan();

            }

            function handleTouchStartDollyRotate() {

                if ( scope.enableZoom ) handleTouchStartDolly();
                if ( scope.enableRotate ) handleTouchStartRotate();

            }

            function handleTouchMoveRotate( event ) {

                if ( pointers.length == 1 ) {

                    rotateEnd.set( event.pageX, event.pageY );

                } else {

                    const position = getSecondPointerPosition( event );
                    const x = 0.5 * ( event.pageX + position.x );
                    const y = 0.5 * ( event.pageY + position.y );
                    rotateEnd.set( x, y );

                }

                rotateDelta.subVectors( rotateEnd, rotateStart ).multiplyScalar( scope.rotateSpeed );
                const element = scope.domElement;
                rotateLeft( 2 * Math.PI * rotateDelta.x / element.clientHeight ); // yes, height

                rotateUp( 2 * Math.PI * rotateDelta.y / element.clientHeight );
                rotateStart.copy( rotateEnd );

            }

            function handleTouchMovePan( event ) {

                if ( pointers.length === 1 ) {

                    panEnd.set( event.pageX, event.pageY );

                } else {

                    const position = getSecondPointerPosition( event );
                    const x = 0.5 * ( event.pageX + position.x );
                    const y = 0.5 * ( event.pageY + position.y );
                    panEnd.set( x, y );

                }

                panDelta.subVectors( panEnd, panStart ).multiplyScalar( scope.panSpeed );
                pan( panDelta.x, panDelta.y );
                panStart.copy( panEnd );

            }

            function handleTouchMoveDolly( event ) {

                const position = getSecondPointerPosition( event );
                const dx = event.pageX - position.x;
                const dy = event.pageY - position.y;
                const distance = Math.sqrt( dx * dx + dy * dy );
                dollyEnd.set( 0, distance );
                dollyDelta.set( 0, Math.pow( dollyEnd.y / dollyStart.y, scope.zoomSpeed ) );
                dollyOut( dollyDelta.y );
                dollyStart.copy( dollyEnd );

            }

            function handleTouchMoveDollyPan( event ) {

                if ( scope.enableZoom ) handleTouchMoveDolly( event );
                if ( scope.enablePan ) handleTouchMovePan( event );

            }

            function handleTouchMoveDollyRotate( event ) {

                if ( scope.enableZoom ) handleTouchMoveDolly( event );
                if ( scope.enableRotate ) handleTouchMoveRotate( event );

            }

            function handleTouchEnd( ) { // no-op
            } //
            // event handlers - FSM: listen for events and reset state
            //


            function onPointerDown( event ) {

                if ( scope.enabled === false ) return;

                if ( pointers.length === 0 ) {

                    scope.domElement.setPointerCapture( event.pointerId );
                    scope.domElement.addEventListener( 'pointermove', onPointerMove );
                    scope.domElement.addEventListener( 'pointerup', onPointerUp );

                } //


                addPointer( event );

                if ( event.pointerType === 'touch' ) {

                    onTouchStart( event );

                } else {

                    onMouseDown( event );

                }

            }

            function onPointerMove( event ) {

                if ( scope.enabled === false ) return;

                if ( event.pointerType === 'touch' ) {

                    onTouchMove( event );

                } else {

                    onMouseMove( event );

                }

            }

            function onPointerUp( event ) {

                if ( scope.enabled === false ) return;

                if ( event.pointerType === 'touch' ) {

                    onTouchEnd();

                } else {

                    onMouseUp( event );

                }

                removePointer( event ); //

                if ( pointers.length === 0 ) {

                    scope.domElement.releasePointerCapture( event.pointerId );
                    scope.domElement.removeEventListener( 'pointermove', onPointerMove );
                    scope.domElement.removeEventListener( 'pointerup', onPointerUp );

                }

            }

            function onPointerCancel( event ) {

                removePointer( event );

            }

            function onMouseDown( event ) {

                let mouseAction;

                switch ( event.button ) {

                    case 0:
                        mouseAction = scope.mouseButtons.LEFT;
                        break;

                    case 1:
                        mouseAction = scope.mouseButtons.MIDDLE;
                        break;

                    case 2:
                        mouseAction = scope.mouseButtons.RIGHT;
                        break;

                    default:
                        mouseAction = - 1;

                }

                switch ( mouseAction ) {

                    case THREE.MOUSE.DOLLY:
                        if ( scope.enableZoom === false ) return;
                        handleMouseDownDolly( event );
                        state = STATE.DOLLY;
                        break;

                    case THREE.MOUSE.ROTATE:
                        if ( event.ctrlKey || event.metaKey || event.shiftKey ) {

                            if ( scope.enablePan === false ) return;
                            handleMouseDownPan( event );
                            state = STATE.PAN;

                        } else {

                            if ( scope.enableRotate === false ) return;
                            handleMouseDownRotate( event );
                            state = STATE.ROTATE;

                        }

                        break;

                    case THREE.MOUSE.PAN:
                        if ( event.ctrlKey || event.metaKey || event.shiftKey ) {

                            if ( scope.enableRotate === false ) return;
                            handleMouseDownRotate( event );
                            state = STATE.ROTATE;

                        } else {

                            if ( scope.enablePan === false ) return;
                            handleMouseDownPan( event );
                            state = STATE.PAN;

                        }

                        break;

                    default:
                        state = STATE.NONE;

                }

                if ( state !== STATE.NONE ) {

                    scope.dispatchEvent( _startEvent );

                }

            }

            function onMouseMove( event ) {

                if ( scope.enabled === false ) return;

                switch ( state ) {

                    case STATE.ROTATE:
                        if ( scope.enableRotate === false ) return;
                        handleMouseMoveRotate( event );
                        break;

                    case STATE.DOLLY:
                        if ( scope.enableZoom === false ) return;
                        handleMouseMoveDolly( event );
                        break;

                    case STATE.PAN:
                        if ( scope.enablePan === false ) return;
                        handleMouseMovePan( event );
                        break;

                }

            }

            function onMouseUp( event ) {

                handleMouseUp( event );
                scope.dispatchEvent( _endEvent );
                state = STATE.NONE;

            }

            function onMouseWheel( event ) {

                if ( scope.enabled === false || scope.enableZoom === false || state !== STATE.NONE && state !== STATE.ROTATE ) return;
                event.preventDefault();
                scope.dispatchEvent( _startEvent );
                handleMouseWheel( event );
                scope.dispatchEvent( _endEvent );

            }

            function onKeyDown( event ) {

                if ( scope.enabled === false || scope.enablePan === false ) return;
                handleKeyDown( event );

            }

            function onTouchStart( event ) {

                trackPointer( event );

                switch ( pointers.length ) {

                    case 1:
                        switch ( scope.touches.ONE ) {

                            case THREE.TOUCH.ROTATE:
                                if ( scope.enableRotate === false ) return;
                                handleTouchStartRotate();
                                state = STATE.TOUCH_ROTATE;
                                break;

                            case THREE.TOUCH.PAN:
                                if ( scope.enablePan === false ) return;
                                handleTouchStartPan();
                                state = STATE.TOUCH_PAN;
                                break;

                            default:
                                state = STATE.NONE;

                        }

                        break;

                    case 2:
                        switch ( scope.touches.TWO ) {

                            case THREE.TOUCH.DOLLY_PAN:
                                if ( scope.enableZoom === false && scope.enablePan === false ) return;
                                handleTouchStartDollyPan();
                                state = STATE.TOUCH_DOLLY_PAN;
                                break;

                            case THREE.TOUCH.DOLLY_ROTATE:
                                if ( scope.enableZoom === false && scope.enableRotate === false ) return;
                                handleTouchStartDollyRotate();
                                state = STATE.TOUCH_DOLLY_ROTATE;
                                break;

                            default:
                                state = STATE.NONE;

                        }

                        break;

                    default:
                        state = STATE.NONE;

                }

                if ( state !== STATE.NONE ) {

                    scope.dispatchEvent( _startEvent );

                }

            }

            function onTouchMove( event ) {

                trackPointer( event );

                switch ( state ) {

                    case STATE.TOUCH_ROTATE:
                        if ( scope.enableRotate === false ) return;
                        handleTouchMoveRotate( event );
                        scope.update();
                        break;

                    case STATE.TOUCH_PAN:
                        if ( scope.enablePan === false ) return;
                        handleTouchMovePan( event );
                        scope.update();
                        break;

                    case STATE.TOUCH_DOLLY_PAN:
                        if ( scope.enableZoom === false && scope.enablePan === false ) return;
                        handleTouchMoveDollyPan( event );
                        scope.update();
                        break;

                    case STATE.TOUCH_DOLLY_ROTATE:
                        if ( scope.enableZoom === false && scope.enableRotate === false ) return;
                        handleTouchMoveDollyRotate( event );
                        scope.update();
                        break;

                    default:
                        state = STATE.NONE;

                }

            }

            function onTouchEnd( event ) {

                handleTouchEnd( event );
                scope.dispatchEvent( _endEvent );
                state = STATE.NONE;

            }

            function onContextMenu( event ) {

                if ( scope.enabled === false ) return;
                event.preventDefault();

            }

            function addPointer( event ) {

                pointers.push( event );

            }

            function removePointer( event ) {

                delete pointerPositions[ event.pointerId ];

                for ( let i = 0; i < pointers.length; i ++ ) {

                    if ( pointers[ i ].pointerId == event.pointerId ) {

                        pointers.splice( i, 1 );
                        return;

                    }

                }

            }

            function trackPointer( event ) {

                let position = pointerPositions[ event.pointerId ];

                if ( position === undefined ) {

                    position = new THREE.Vector2();
                    pointerPositions[ event.pointerId ] = position;

                }

                position.set( event.pageX, event.pageY );

            }

            function getSecondPointerPosition( event ) {

                const pointer = event.pointerId === pointers[ 0 ].pointerId ? pointers[ 1 ] : pointers[ 0 ];
                return pointerPositions[ pointer.pointerId ];

            } //


            scope.domElement.addEventListener( 'contextmenu', onContextMenu );
            scope.domElement.addEventListener( 'pointerdown', onPointerDown );
            scope.domElement.addEventListener( 'pointercancel', onPointerCancel );
            scope.domElement.addEventListener( 'wheel', onMouseWheel, {
                passive: false
            } ); // force an update at start

            this.update();

        }

    } // This set of controls performs orbiting, dollying (zooming), and panning.
    // Unlike TrackballControls, it maintains the "up" direction object.up (+Y by default).
    // This is very similar to OrbitControls, another set of touch behavior
    //
    //    Orbit - right mouse, or left mouse + ctrl/meta/shiftKey / touch: two-finger rotate
    //    Zoom - middle mouse, or mousewheel / touch: two-finger spread or squish
    //    Pan - left mouse, or arrow keys / touch: one-finger move


    class MapControls extends OrbitControls {

        constructor( object, domElement ) {

            super( object, domElement );
            this.screenSpacePanning = false; // pan orthogonal to world-space direction camera.up

            this.mouseButtons.LEFT = THREE.MOUSE.PAN;
            this.mouseButtons.RIGHT = THREE.MOUSE.ROTATE;
            this.touches.ONE = THREE.TOUCH.PAN;
            this.touches.TWO = THREE.TOUCH.DOLLY_ROTATE;

        }

    }

    THREE.MapControls = MapControls;
    THREE.OrbitControls = OrbitControls;

} )();
